Engine Braking

[Kiwi Dave]

I used to do a lot of engine braking. Then I took the advanced safety course and they talked me out of it.

 

I'm curious to know why the advanced safety course discouraged you from using engine braking (in the quest of better safety?).

 

For most street work, I try to avoid the use of brakes, chosing instead to use the throttle to control my speed, changing down gears if necessary. It's not the fastest way to get around corners, but it gives me the most pleasure.

 

Am I a dangerous rider? (Those who know me, don't answer that!)

[gthyni]

I think it all depend on what situation we are talking about.

- cruising downtown and engine brake before turning in a crossing

- racing at high speed shifting down a couple of gears before cornering

 

in the 1st situation it is no problem except it is good idea to apply a little

break to flash the break light at vehicles behind you.

 

in the 2nd situation it put heavy pressure and the engine and gearbox

and you could easily loose grip on the rear.

[Baldini]

It's like all this how you should ride stuff - racetrack & road have different requirements. Seems to me these California Superbike people are too dogmatic, confuse people with track technique that is often innapropriate on the road, knee dragging, leaning off inside, weighting pegs, countersteering - it's all only relevant at extremes...while you're trying to do all that suff watch out for that lorry heading your way just past that pile of cow shit there...Ride how you feel comfortable. I've never got me knee down but I've overtaken people who were dragging knees, only time I ever tried I was concentrating so hard I lost me way completely & ended up on the infield. I've always used engine braking on 4 strokes & I can't see how running into a corner clutch in can be safer - you've disconnected two of the main controls on the bike - engine & rear wheel..

 

Slipper clutches are surely only there to minimise effects of engine braking. In racing, brakes are much more accurate, precise, effective way of controlling bike which has all load on front wheel anyhow, & is slowing much harder than you'd usually be doing on the road except in an emergency. But perhaps that's the point...If you have to stop suddenly in an emergency brakes are the only way, rear wheel's likely gonna be up in the air anyhow (well maybe not the v11...) engine braking is pretty irrelevant - is that what they were getting at? - if you always rely on engine braking to slow you may never learn to use the brakes properly to stop quickly. What will happen in an emergency? It's worth practicing hard braking to stop motorcycle & learn to separate it from engine braking, find where front tyre can grip to. Try racing a two stroke for full effect...

 

As to wear, I don't know much about the mechanics of it but it stands to reason if you're loading a part in motion there'll be some wear - lubrication isn't perfect. Price you pay.

 

Now what exactly is piffle.

 

KB, the ignorant one, Cymru

[pete roper]

In my beloved State, (NSW) they are actually FAILING people on car driving tests if they slow down using the engine rather than the brakes, even if they touch the brakes to indicate to following traffic they are slowing. These complete fuckwits who have instituted this program say that the safest way to stop is to brake in a high gear, (4th/5th) until such point that the engine begins to lug at which point the clutch should be depressed and a full halt achieved by brakes alone. Only when the machine is either stationary or at it's lowest possible speed should a lower gear be selected!!!!!!!! I'm sorry but this is dangerous cretinism of the highest order. What happens if the driver suddenly needs to accelerate and they are in a high gear? What happens to the suspension and transmission loadings when traveling in 'Angel Gear'?

 

It is trully a frightening example of unskilled and non understanding people being allowed to make the rules.

 

As for motorbikes? The differences between a light, chain driven, repli-racer with a high F/R bias and a machine like a Guzzi are many and manifest. trying to ride a Guzzi like an RGV is not only stupid, its fruitless too. I still maintain that the best way to get a Guzzi, any Guzzi, round a corner fast is to hit the picks as late as you can and use a combination of rapid downchanges with engine braking, missing some gears if neccessary, to get all the slowing down done BEFORE you tip it in. Make sure you're in the correct gear for your entry speed and then wind it on and use the torque to push you out of the corner.

 

I can't imagine that any correctly set up V11 that hasn't been modified or extensively lightened would be able to break traction in the dry with *most* riders on board unless they are super-keen or the bike is set up wrong. Steering with the back just isn't an issue, lets face it it isn't for most people on the road. I know that I have to get really stupid to break traction with my old hot-rod and it runs a skinny 120 crossply on the back, and , no, I don't pretend to steer it with the rear wheel. Shit myself when it lets go? Yes! Steer? No!

 

Like it or not a Guzzi is an old fashioned motorbike in just about every way, including the way they steer and handle. To me that is a bonus. I think a repliracer or overpowered pig is a stupid thing to try and take on the road. If you want to go racing go to a frigging race track. Racing has no place on the public road. That isn't to say fast riding doesn't have a place, my licence will attest to my flaunting of the stupid road laws, but racing is a recipe for disaster!

 

While not usning engine braking *may* have merit is some situations,most particularly on a racetrack, removing the drive forces from the handling and roadholding eqation is an unmitigated disaster, especially with a comparatively heavy, rear wheel drive, single track vehicle! You can play biggus-dickus, play race/pysicist till you're blue in the tits but I'm telling you you'll get round corners quicker and have better overall control of your vehicle if you keep the engine connected with the back wheel as much as possible, be it under drive or on the overun.

 

Pete

[gthyni]

Agreed with most KB and Pete say,

but this aussie disagrees

 

A few points:

 

- You can ride a V11 pretty hard, you have a better power range

then a RGV, but if you keep it over 5500-6000 rpm it really moves

My naked 2001 a quiet responsive to steering too, especially after

I replace the Bitubo steering damper with an Öhlins unit.

And the breaks are better than what most japanese sport bikes have.

 

- The secret of cornering (according to Keith Code) is to be done with

breaking before the bend and slowly opening the throttle while going into it.

The reason is that the diameter of the tyre is less when leaning so

the same rpm effectively put some (engine) break on the rear wheel

and we don't want that.

 

- We all use countersteering, consiously or not. Being aware of the technic

help us do the right thing when getting into a critical situation.

 

- Don't try dragging a knee for it own sake,

when you get comfortable enough to lean over

that much it happens by itself. And no, I have not

done it on the V11 since I didn't trust the tyres I

had on enough and I don't really see the point.

Most fun roads around here is a bit to bumpy for

stunts like that.

 

 

I again recommend "A twist of a wrist II",

part I is mostly racing related, part II give good advise

usable for every rider. It is not about running fast, it is

about better control and saver riding.

[Motomonster]

I used to do a lot of engine braking. Then I took the advanced safety course and they talked me out of it.

 

I'm curious to know why the advanced safety course discouraged you from using engine braking (in the quest of better safety?).

 

For most street work, I try to avoid the use of brakes, chosing instead to use the throttle to control my speed, changing down gears if necessary. It's not the fastest way to get around corners, but it gives me the most pleasure.

 

Am I a dangerous rider? (Those who know me, don't answer that!)

I use my throttle to control my speed in traffic, but if I'm coming to a stop, I use my brakes. I used to downshift and let the engine slow me and then down shift again, etc. But at the safety course, they said it's best to "remove the engine from the stopping equation". So I just use the brake and downshift into neutral. They claim there is less engine wear this way, plus it forces you to practice your braking techniqe every time you stop. Also, it is a lot less work at every stoplight.

[Baldini]

it forces you to practice your braking techniqe every time you stop

I think this is what this is about.

there's a lot of people driving who regard it pretty much as like watching the TV...mmm...what channel we on?

KB,Cymru

[amazon]

I was always taught that pulling in the clutch and coasting meant you were basically out of control - you fail your car test for doing this !!!!!! I have always used engine braking it is one of the things I love about V twins. My Mille goes round corners tons faster if you go down a gear and accelerate round them keeping everything "tight". To high a gear and she almost feels wobbly! Can't ever profess to getting my knee down but I have watched a California going up the inside of a ZXR whose rider had his knee down on a corner! Totally pissed off the ZXR rider!!!

[Motomonster]

I'm getting the sense that we all mean something different by the term "engine braking".

[belfastguzzi]

In my beloved State, (NSW) they are actually FAILING people on car driving tests if they slow down using the engine rather than the brakes, 

the safest way to stop is to brake in a high gear, (4th/5th) until such point that the engine begins to lug at which point the clutch should be depressed and a full halt achieved by brakes alone. Only when the machine is either stationary or at it's lowest possible speed should a lower gear be selected!!!!!!!!

Yes, seems completely barking, especially on a bike where you have to go sequentially through the box. It's easier to see this technique using a car box where you can move from 5th to second in one move.

 

But with the bike it's too easy to coast along, disengaged, then find the wrong gear, or a false neutral, just when you need to pull away –

 

– he said with feeling, after dropping the bike at a junction doing 0mph yesterday

 

One bent brake lever later – I think it's a sign: the bike's telling me not to use the brakes.

 

There's probably no answer to this question for those of us under 6', but has anyone got a technique for righting the bike when it has gone past the point of balance and you're standing with one foot on the ground and desperately trying to heave it up again by the handlebars?

[Janusz]

I'm getting the sense that we all mean something different by the term "engine braking".

Same here...

 

At one extreme would be just grabbing the clutch and coasting while shifting to neutral or not and using your brakes only. The other extreme is, while braking or not, shifting down one gear at the time and letting the clutch out, aka typical engine braking.

 

I do not think any of these technics is proper or useful on the street. When I have to slow down on the street, either leisurely or more forcefully or in an emergency even, I leave the clutch and gear lever alone and JUST BRAKE. Then shift quickly to a proper gear and just keep going into turn or whatever.

 

Or just grab the clutch and stop completely and then shift into first or neutral.

[Baldini]

watched a California going up the inside of a ZXR whose rider had his knee down on a corner

 

wasn't a trackday at Ty Croes...?

 

KB,Cymru

[Lex]

This seems to have become a pick on bureaucrats (nice to know the Aussie type are as dumb and arrogant as the red white and blue types ) and how to ride thread but I just have to ask Fonzi if he really believes:

 

Please also keep in mind that during the initiation of the intake stroke, the piston is pushing exhaust from the cylinder, so it does see some loading.

 

"Some loading" is an interesting term, I guess there is some loading with at least one valve open, 360 degrees after the combustion event but I find it hard to believe it would be any more than with the throttle closed when the engine is running, abet only at idle.

 

I have to wonder if this "stress on the engine by using engine braking" thing is based on two-cycles, they don't have a the high tensile loading of the rod, crank and piston like four-cycles since they don't have an idle trip past top dead center. Well, mine did but only until I learned how to jet them. In that case I can see some basis but in our engines I can't see any extra stress unless the rider is a moron, down shifting so early the engine is pulled out of its safe operating range.

 

Lex

[Guest Brian Robson]

Janusz...you shift quickly on a V11?

[Guest Fonzarelli]

I have to wonder if this "stress on the engine by using engine braking" thing is based on two-cycles, they don't have a the high tensile loading of the rod, crank and piston like four-cycles since they don't have an idle trip past top dead center.

I don't remember this being an issue at idle.

 

The G loads on the reciprocating parts increase with RPM (as does piston speed, regardless if it's a two stroke or a four stroke) so this issue only becomes serious when operating at high RPM's. Piston speed at idle is nothing to be concerned about.

 

I am not trying to convince anyone here that the World is flat. This issue of high RPM decelerating under a closed throttle does actually become a reality to the reciprocating parts and can be quite devastating if done over a given period of time.

 

Certain engine design perameters certainly do influence the stresses more than others.

 

-Under square bore to stroke ratios (the stroke being longer than the diameter of the bore.

 

-Heavy pistons and pins (the more weight required to instantly change direction creates more tensile load on the connecting rods)

 

-High RPM's

 

Anyway, my original intent was to add some new information to the original post. Code might have given a very general discription of the consequences of engine braking, but there is some reality in his qoute.

 

Best Regards,

 

Fonz